"The UN has to show that we can be not just united in condemnation, but united in action, acting in a way that lives up to the UN's founding principles and meet the needs of the people."

"You can sign every human rights declaration in the world, but if you stand by and watch people being slaughtered in their own country, when you could act, then what are those signatures really worth?"

The prime minister did not mention the Palestine vote during the speech.

A similar speech praising the Arab Spring yesterday from US president Barack Obama failed to mention the vote, even though he has said he will veto any bid for statehood at the council stage.

Britain has still not made it clear how it will respond if Palestinian president Mahmoud Abbas manages to get the bid to the 15-member security council.

Labour is lobbying hard for a 'yes' vote with Douglas Alexander writing letters to the Foreign Office while former foreign secretary Jack Straw drums up support among MPs.

Comments earlier this week from Nick Clegg suggest there were divisions at the top of government about how to react to the bid.

While Britain has been trying to position itself as a supporter of change in the region, the foreign secretary is known to be uncomfortable with the vote.

"It will just lead to confrontation," Mr Hague commented.

While Palestine's bid to secure full statehood looks set to fail given the US' pledge to veto it, the Palestinian Authority could still gain greater recognition at the UN with majority support in the general assembly, an option supported by French president Nicholas Sarkozy.

"Who could doubt that a veto at the security council risks engendering a cycle of violence in the Middle East?" the French leader warned the UN.

Mr Cameron will fly from New York for a meeting with Canadian prime minister Stephen Harper before addressing the Canadian parliament.